Re: [PATCH v2 07/11] kbuild: rust_is_available: fix confusion when a version appears in the path

[Nathan Chancellor <nathan@kernel.org>]

On Fri, Jun 16, 2023 at 02:16:27AM +0200, Miguel Ojeda wrote:
> `bindgen`'s output for `libclang`'s version check contains paths, which
> in turn may contain strings that look like version numbers [1][2]:
> 
>     .../6.1.0-dev/.../rust_is_available_bindgen_libclang.h:2:9: warning: clang version 11.1.0  [-W#pragma-messages], err: false
> 
> which the script will pick up as the version instead of the latter.
> 
> It is also the case that versions may appear after the actual version
> (e.g. distribution's version text), which was the reason behind `head` [3]:
> 
>     .../rust-is-available-bindgen-libclang.h:2:9: warning: clang version 13.0.0 (Fedora 13.0.0-3.fc35) [-W#pragma-messages], err: false
> 
> Thus instead ask for a match after the `clang version` string.
> 
> Reported-by: Jordan Isaacs <mail@jdisaacs.com>
> Closes: https://github.com/Rust-for-Linux/linux/issues/942 [1]
> Reported-by: Ethan D. Twardy <ethan.twardy@gmail.com>
> Closes: https://lore.kernel.org/rust-for-linux/20230528131802.6390-2-ethan.twardy@gmail.com/ [2]
> Reported-by: Tiago Lam <tiagolam@gmail.com>
> Closes: https://github.com/Rust-for-Linux/linux/pull/789 [3]
> Fixes: 78521f3399ab ("scripts: add `rust_is_available.sh`")
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Nathan Chancellor <nathan@kernel.org>

> ---
>  scripts/rust_is_available.sh | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh
> index 7e0368babe64..810691af66eb 100755
> --- a/scripts/rust_is_available.sh
> +++ b/scripts/rust_is_available.sh
> @@ -157,9 +157,7 @@ fi
>  # of the `libclang` found by the Rust bindings generator is suitable.
>  bindgen_libclang_version=$( \
>  	echo "$bindgen_libclang_output" \
> -		| grep -F 'clang version ' \
> -		| grep -oE '[0-9]+\.[0-9]+\.[0-9]+' \
> -		| head -n 1 \
> +		| sed -nE 's:.*clang version ([0-9]+\.[0-9]+\.[0-9]+).*:\1:p'
>  )
>  bindgen_libclang_min_version=$($min_tool_version llvm)
>  bindgen_libclang_cversion=$(get_canonical_version $bindgen_libclang_version)
> -- 
> 2.41.0
>